Only Xp means?
If u want to delete Fedora, u need to delete the Linux partitions!
You may try Partition Managers to partition ur disk and then try Window's disc. If possible try booting with another CD/DVD Writer/Drive!

i dnt understand one thing why u people need to install GRUB in the MBR(master boot loader). Its a common problem when u try to boot from XP cd nd GRUB dnt allow u to do this. One shud make ur PC dual boot for both linux and windows.. then u dnt have to face such problems..there are three processes by which u can use Ntldr for deciding the menu for OS..u dnt have to give the whole power to GRUB. The three processes are:-
1)Use dd to copy GRUB stage1 to a binary file
2) use BOOTPART command
3) use GRUB for DOS application

but itz ok...i think there is no point in mentioning all these things over here..i will write an article on that so that no computer user has to face such problem in future regarding GRUB. Now for ur case try vista, windows 7 etc etc nd finally if u cnt do nething then full format ur computer...

u can do one thing which i did once when i faced the same problem:-
1) boot with ur fedora DVD
2) format the fedora partition just to give it the assurance that u r going to do the fresh installation.
3) after formatting the partition to ext3 proceed to the new installation.
4)once the installation starts take out ur DVD quickly , reboot and quickly insert the XP CD.

u can do one thing which i did once when i faced the same problem:-
1) boot with ur fedora DVD
2) format the fedora partition just to give it the assurance that u r going to do the fresh installation.
3) after formatting the partition to ext3 proceed to the new installation.
4)once the installation starts take out ur DVD quickly , reboot and quickly insert the XP CD.

voilla u r done...but u will lose the fedora...

fedora is working for me
i want to install xp without deleting linux partitions

u can do one thing which i did once when i faced the same problem:-
1) boot with ur fedora DVD
2) format the fedora partition just to give it the assurance that u r going to do the fresh installation.
3) after formatting the partition to ext3 proceed to the new installation.
4)once the installation starts take out ur DVD quickly , reboot and quickly insert the XP CD.